Can someone help with understanding viral load results?

[cwar]

Today we found out that when my husband had his viral load done the results came back at 1.27e to the 6th.  Would someone be kind enough to tell me what this means please?  

Thank you.

[Bill1954]

Yeah; I’ve read this article before. It does appear loaded for Pegasys, but there’s no reason that I can see that it wouldn’t apply to Pegintron or any other IFN for that matter. It appears that this is the model that identifies the greatest difference in SVR rates. Personally, I had a very low VL (never exceeding 150,000 IU/mL), and had a dickens of a time achieving SVR. Of course, the old saw still applies; “statistics never lie, but only liars use statistics” :o).

Bill

[portann]

Thanks, Bill.  Did you read the whole thing? It surprised me.

[m_strings]

Thanks Bill!

[portann]

Hi M,

Thank you for citing the 800, 000 dividing point between high and low. That number comes from the Janis site, quoted from Dr. Pearlman ( the doctor of a friend of mine). The table I posted is also from the site (!!), maybe outdated but I'm not sure. Zazza is really up on these things, btw.

The point to convey, though, is that viral load is only significant while treating.

Hi C,

The viral load in your husband's case was expressed exponentially.  Zazza is the numbers person here on the forum, so if you're lucky enough to get a reply from her, you're in the best hands possible. And I repeat, the viral load is only significant while treating.

[nygirl7]

Aside from the "number" explanation first off know that most off VL means nothing as to determining how his liver is doing or how long he would need to do treatment.  For those things you need to find out what his genotype is and what grade/stage of liver damage he has. You find the second part out via a biopsy (which sounds dreadful but is not painful as your liver has no nerves to feel any pain so it's just like a needle pretty much).

What we do use VL for is once we start treatment it is a tool used to determine how quickly the virus is being killed off and once you are undetectible.....for example a geno 1 (whch is most common in the USA) treats for 48 weeks as a rule - you need to be UND by week 12 otherwise now commonly you extend to week 72. But if you are not UND by week 24 then treatment isn't working and it's time to stop and find a new alternative. Things like that.

The key things to determine therefore are what his liver enzymes are doing (alt and ast on his test reports) biopsy results and genotype.

Try to make sure they give you a copy of every single test result he has done.  Then you can ask direct questions in here. Most often doctors talk so fast and explain so little it's much easier.

good luck.

[Bill1954]

I think I can shed some light on this disparity.

The cutoff for low viral load was redefined by the European Association for the Study of the Liver (EASL) in April 2007 at their Barcelona convention. The new standard is 400,000 IU/mL. Here’s the link for anyone interested; I believe this is a credible source. Unfortunately, Janis and Friends isn’t always edited in a timely manner:

http://www.natap.org/2007/EASL/EASL_41.htm

Bill

[m_strings]

Portann: According to that link, anything over 800,000 when expressed as IU/ml is high.  Anything over 2 million when expressed as copies/ML is high.  I think it's important to distinguish the different ways of expressing viral load.  (I wish this was consistent because it's quite confusing.)  

Per that site:

Interpreting Viral Load Test Results
HCV viral load is often reported as low or high.
Expressed as copies/mL:
·Low: less than 2 million copies
·High: more than 2 million copies

Expressed as International Units (IU/mL):
·Low:less than 800,000 IU/mL
·High:more than 800,000 IU/mL

Three types of viral load tests are commonly used: PCR, TMA, bDNA
Quantitative viral load is measured in IU/mL (the current standard); old records may report copies/mL
While I didn't find an exact way to convert IU to copies and visa versa, I found this estimated conversion from the Hepatitis C Caring Ambassadors Program:

With PCR:  convert IU/mL to copies/mL
multiply by 2.7

With TMA: convert IU/mL to copies/mL
multiply by 5.2

I hope this is useful.

[portann]

That is a medium viral load of 1,270,000 iu/ml.

See http://janis7hepc.com/Viral_Loads.htm#Viral%20load%20chart for further explanation. It's a great site to learn about HCV. The following is copied from there:

Exponential format:

Large numbers are often expressed in exponential form, that means a number, multiplied by 10 with an exponent. To convert this to normal numbers, append as many zeroes to a "1" as the exponent says, and multiply this with the number.

Hepatitis C viral (HCV) load does not correlate with the histological
evolution of the disease, and use of viral RNA quantification as a predictor
or determinant of severity of this disease is incorrect and of relative
value.

It is not useful to monitor hepatitis C viral loads when you are not receiving any treatment.

High viral loads do not necessarily indicate severe disease in hepatitis C.

The HCV RNA or viral load will vary significantly from month to month in patients not receiving interferon/ribavirin, but this does not mean anything.

Do not panic if you hear the viral load is in six or seven figures as this is the usual range with hepatitis C.

below 200.000
very low
  
200,000-1,000,000
low
  
1,000,000-5,000,000
medium
average viral load at 3,200,000 eq/ml

5,000,000-25,000,000
high

above 25,000,000
very high